Barrier_IIA_Feb_07_Testing_Report_061207.pdf

Dispersal Barrier IIA February 2007 Sparking Potential, Corrosion Potential, and Electric Field Strength Testing

Prepared By:

U.S. Army Corps of Engineers, Chicago District 111 North Canal Street, Chicago, Illinois 60606

U.S. Army Corps of Engineers, Engineer Research and Development Center Construction Engineering Research Laboratory

P.O. Box 9005, Champaign, Illinois 61826

June 12, 2007

Dispersal Barrier IIA February 2007 Sparking Potential, Corrosion Potential, and Electrical Field Strength Testing

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EXECUTIVE SUMMARY

Initial start-up and safety testing at Barrier IIA indicated that the barrier's electric field could lead to sparking during fleeting activities at the neighboring Midwest Generation fleeting area.

Various tests were completed in 2006 to attempt to identify an operating configuration that eliminated this sparking risk. The 2006 tests are described in a previous USACE report, "Dispersal Barrier IIA Electric Field Strength and Sparking Potential Testing" (Attachment 1).

USACE then developed "Test Plan for Further Electric Field Strength and Sparking Testing, Aquatic Nuisance Species Dispersal Barrier IIA" (Attachment 2). This plan proposed further electric field strength mapping and sparking potential and corrosion potential tests for the most promising barrier operating configurations. The additional testing was completed in February 2007 and is described in this report.

The February 2007 testing results indicate that while there is still a measurable electric field beyond the Regulated Navigation Area established for the barriers for all tested barrier operating configurations, it is not of sufficient strength to cause sparking during fleeting operations. A barrier operating configuration is recommended for which Barrier IIA can safely be operated at a maximum in-water voltage of 1 volt/inch if bow boats are provided for red flag tows that are long enough to simultaneously be over the active IIA electrodes and south of the RNA. The recommended configuration also has no impact on the corrosion potential of barges moored in the fleeting area.

Additional sparking potential testing for long tows should be completed to verify the need for bow boats. Additional sparking and corrosion potential testing should also be completed to verify the safety of operating at higher in-water voltages than 1 volt/inch. The U.S. Navy Experimental Diving Unit is completing a study on the physiologic effects the barrier would have on a person immersed in the electrified water. The results of this study will be released in a separate report.

INTRODUCTION

The U.S. Army Corps of Engineers (USACE) – Chicago District is operating a demonstration electric field-based aquatic nuisance species dispersal barrier (Barrier I) in the Chicago Sanitary and Ship Canal (CSSC), Romeoville, Illinois. After an electrical discharge-related incident in the vicinity of the barrier was reported in 2004, USACE and the U.S. Coast Guard coordinated to complete a series of safety tests at the demonstration barrier. Based on the results of these tests, the Coast Guard established a Regulated Navigation Area (RNA) between Mile Marker 296.1 (the north side of the Romeo Road Bridge) and Mile Marker 296.7 (the south side of an aerial pipeline).

USACE is also constructing a second, more permanent dispersal barrier (Barrier II) in the CSSC.

Barrier II is located 800 feet downstream of the demonstration barrier and is also located within the RNA. It is being constructed in two phases. Each phase can be operated independently, but the ultimate goal is to operate both at the same time. The first phase (IIA) consists of construction of two sets of underwater electrode arrays and one control house (pulser building).

The second phase (IIB) consists of construction of a second control house that will allow both

Page 3 of 34 6/11/2007 sets of arrays to be operated at the same time. Figure 1 shows the relative locations of Barrier I and Barrier II.

The Barrier IIA control house was completed and fully connected to the southern set of electrode arrays in the spring of 2006. Initial measurements of the strength and extent of the electric field generated by Barrier IIA showed that the field extended beyond the southern end of the RNA.

This generated concerns that the field would negatively impact operations in a Midwest Generation fleeting area located approximately 150 feet south of the RNA. Subsequent sparking potential tests showed that this electric field could lead to sparking between barges in the fleeting area. Therefore, physical and operational changes were evaluated to reduce the electric field beyond the RNA.

It was determined that placing electrically conductive material in the canal between the barrier and the southern end of the RNA would reduce the electric field extent. A grounding system consisting of interconnected steel blast mats was constructed on the canal bottom between Barrier IIA and the Romeo Road Bridge. With the blast mat system in place, additional electrical field measurements were taken while varying barrier operating parameters and the way the mats were grounded. These measurements identified several barrier operating configurations that were most successful at reducing the spread of the electric field beyond the RNA. Figure 2 shows Barrier IIA and nearby features.

The previous testing at Barrier IIA is described in detail in "Dispersal Barrier IIA Electric Field Strength and Sparking Potential Testing"; a USACE report dated 24 October 2006. USACE then developed "Test Plan for Further Electric Field Strength and Sparking Testing, Aquatic Nuisance Species Dispersal Barrier IIA," dated 3 November 2006. This plan proposed further electric field strength mapping and sparking potential and corrosion potential tests for the most promising barrier operating configurations. The additional testing was completed in February 2007 and is described in this report.

EXPERIMENTAL APPROACH

On 27 and 28 February 2007 test were completed to:

• Determine whether sparking would occur between barges during typical fleeting operations at the fleeting area while Barrier IIA is being operated.

• Measure the voltage potential differences between barges during the sparking potential testing to attempt to determine a relationship between potential differences and sparking.

• Determine if operation of Barrier IIA will increase the corrosion rate of barge hulls for barges moored in the fleeting area.

• Complete electric field strength mapping for barrier operating configurations that might be used for longer-term barrier operation.

The canal was closed to through-traffic by the U.S. Coast Guard during all testing. All barges used in testing were fully loaded to achieve maximum hull exposure underwater. Wire rope was

Page 4 of 34 6/11/2007 used to assemble the moving tow and connect all moored barges to each other. Air and water temperature, relative humidity, and water conductivity were recorded during testing.

Sparking Potential Testing

Four barge/tow scenarios were utilized for sparking potential testing: connecting barges in series (Figure 3), connecting barges in parallel (Figure 4), inserting a single barge into a tow (Figure 5), and an angled tow configuration (Figure 6). The first three scenarios simulated various ways of assembling a tow. The angled tow configuration simulated a potential collision where a down-bound tow loses control and moves into the fleeting area. The angled tow configuration was not included in the November 2006 test plan, but was added to the testing to provide a more direct comparison to the angled tow tests completed in April 2006 when sparking was first observed.

Barrier IIA was operated in three different configurations for each of the four barge/tow scenarios. These configurations were identified as the most promising operating configurations to reduce field extent and sparking potential in previous testing and are called ‘I Normal’, ‘I Synchronous’, and ‘E Synchronous’. The physical configuration of the barrier and blast mat system for configurations ‘I’ and ‘E’ are shown in Figures 7 and 8. As originally designed, the S1/S2 arrays and S3/S4 arrays pulsed independently. This is considered "Normal" operation.

"Synchronous" operation is when the S1/S2 arrays and S3/S4 arrays pulse at the same time and power. The November 2006 test plan also proposed testing configurations ‘F’ (floating) and ‘F’ (grounded). However, further consideration determined that these configurations might not be desirable for deterring fish so they were dropped from the testing plan.

As explained in the summary report on previous testing, sparking only occurs when barges contact and then separate. Therefore, for each barge/tow scenario, the moving tow was placed in close proximity to the moored barge that it was to contact. The contact points are shown on Figures 3 through 6. The tow then slowly made contact with the moored barge and slowly moved away. These contacts are called "bumps" in this report. At least two bumps were also completed for each barrier operating configuration. In addition, bumps were completed for each barge/tow scenario with the barrier off to obtain a "background" comparison. During the making and breaking of contact, Corps, Coast Guard, and tow company personnel were positioned to look for sparking between barges. Voltage potential differences between all barges were measured throughout this process.

For each tow assembly scenario and each barrier configuration, the sparking potential tests were first done with the barrier operating at a maximum in-water voltage gradient of approximately 1 volt/inch. If no sparking was observed, an attempt was made to increase the barrier operating voltage to attempt to determine the level at which sparking began. However, due to high water conductivity and barrier equipment limitations, it wasn’t possible on the testing days to operate Barrier IIA at levels higher than approximately 2 volts/inch for the normal operating configuration and 1.5 volts/inch for the synchronous operating configurations.

Corrosion Potential Testing

Corrosion potential was measured on the northern moored barge during the barges in parallel test scenario (Figure 4). Hull voltage potential was measured between silver/silver chloride half-cell

Page 5 of 34 6/11/2007 reference electrodes mounted on the northeast corner of the barge. Measurements were taken with the barrier off, to measure background corrosion potential, and with the barrier operating in the ‘I Normal’ configuration at a maximum in-water voltage gradient of approximately 1 volt/inch. The northern-most barge was chosen because it is the worst case for corrosion since it is closest to the barrier.

The November test plan proposed corrosion potential testing for the other barrier operating configurations as well. However, due to time restrictions it was only possible to test for one operating configuration. Configuration ‘I Normal’ was chosen as it is considered the most desirable potential operating configuration.

Electric Field Strength Mapping

Electric field strength mapping was completed for all of the operating configurations and power levels used in sparking potential testing. To map the strength and extent of the electric field generated by Barrier IIA, an array of sensors was attached to a Boston Whaler fiberglass boat. A small fiberglass boat was used to eliminate field perturbations that could be caused by a metal hull and to allow reasonable maneuverability. The sensors used were highly sensitive silver/silver chloride half-cells. The half-cells were mounted on nylon ropes secured to a wood framework clamped to the boat in a grid configuration as shown on Figure 9. Two sets of half-cells were suspended at four depths (2, 4, 7, and 15 feet) at opposite ends of the boat spaced 17 feet, 4 inches (208 inches) apart horizontally. The half-cell sensors were connected to a data acquisition system for automated recording of voltages measured. The voltage difference between the two half-cells at the same depth divided by the separation distance of 208 inches equals the horizontal electric field strength at that depth in volts/inch.

Once the barrier was activated, the boat traveled slowly over the barrier on the measurement paths shown on Figure 10. Data collection continued for several hundred feet both up and downstream of the barrier itself to determine the full extent of the field. Electric field strength readings for all mapping were geo-referenced by placing global positioning systems (GPS) on the bow and stern of the boat. By simultaneously recording geospatial data from the bow and stern, boat position, including corrections for lateral drift, could be established at any time during mapping. An appendix to this report provides more information on the instrumentation used.

RESULTS

Sparking Potential Testing

Table 1 lists the series of sparking potential tests that were completed at Barrier IIA on 27 and 28 February 2007. The first column of Table 1 lists the date and time the test was completed; the Configuration is a letter assigned to the barrier’s physical configuration and electrical operating parameters for that test; the Figure Number refers to an illustration of the physical configuration of the barrier; the Operating Parameters column describes the barrier electrical configuration, pulser voltage, and pulser current during operation; and Observations and Notes describes any other important observations and details of the test. Table 2 reports the peak voltage gradients at the contact point between the moving and fixed barges for each test and notes whether sparking was observed. The voltage potential Table 3 reports the weather conditions and water conductivity on the testing days.

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No voltage potential differences were observed between the moored barges during testing. This again confirms the conclusion from previous testing at the demonstration barrier and Barrier IIA that voltage potential differences do not develop between barges that are connected with wire rope.

Sparking was observed in only one of the tests (test run 13), the barges in parallel tow assembly scenario (Figure 4) with Barrier IIA operating in configuration ‘I Synchronous’ at a maximum voltage gradient over the barrier of 1 volt/inch. This sparking was observed during two of five “bumps”. When the voltage for configuration ‘I Synchronous’ was increased to approximately

1.5 volts/inch, no sparking was observed during two “bumps”. The canal closure period expired before additional “bumps’ could be done for the 1.5 volts/inch scenario.

Corrosion Potential Testing

Table 4 reports the results of the corrosion potential testing. Table 5 shows generally accepted criteria for corrosion rates for steel in contact with fresh water measured with silver-silver chloride reference electrodes. These results indicate that there is minimal change in corrosion potential when Barrier IIA is operating at a maximum in-water voltage gradient of 1 volt/inch compared to when the barrier is off.

Electric Field Strength Mapping

Table 6 lists the series of electric field strength mapping runs that were completed at Barrier IIA on 28 February 2007. The results of these mapping runs are graphically summarized in Figures 11-17, which were generated by combining the field strength measurements and GPS location data. The field strength measurements are grouped into range bands, which are represented by differing colors. Figure 11 illustrates typical background conditions, indicating the field strength measurements taken while Barrier IIA was not energized. Figures 12 and 13 show the field strengths for the ‘I Normal’ configuration. These figures indicate voltages in the 250-500 millivolts/inch range between the active electrodes and both the Barrier IIB electrodes to the north and the blast mats to the south. Figures 14 through 17 show the field strengths for the ‘I Synchronous’ and ‘E Synchronous’ configurations. These figures indicate lower voltages between the active electrodes and both the Barrier IIB electrodes to the north and the blast mats to the south for the synchronous configuration compared to ‘I Normal’.

Table 7 lists the electrical field strength measurements at the south end of the Romeo Road Bridge by lateral location, depth, and barrier operating configuration. Figure 18 provides a graphic representation of the same information. The +/- value on the table and the bars extending above and below each point on the figure represent one standard deviation above or below the peak value. Field strength measurements were recorded above and below the values represented by the bars, but not included for the sake of comparison between data sets.

DISCUSSION

The observation of sparking during the 27 February Run 13 does not appear to be related to the operation of the barrier. First, sparking was only observed in two of five attempts while barrier operation was being held constant. These sparks were small "pops". If the sparking was related

Page 7 of 34 6/11/2007 to barrier operation, then increasing the barrier voltage and current should have resulted in more consistent and larger, more noticeable sparking. However, operating at a higher voltage in Run 14 did not produce any sparking. Also, during many of the other test runs over the two days, the barrier output voltage and current and the potential differences between the contacting barges were higher than in Run 13, but no sparking was observed. Therefore, it may be concluded that the sparks observed occasionally in Run 13 were generated by some source other than the barrier.

In the April 2006 angled tow sparking potential testing at Barrier IIA, sparking occurred for voltage potential differences between barges of 0.8 to 5 volts. For the angled tow configuration sparking potential tests (Figure 6) on 28 February, the voltage potential differences ranged from

3.4 to greater than 10 volts, but no sparking was observed. The most likely explanation for the elimination of sparking even though the voltage potential differences between barges is higher than in the 2006 tests is that the blast mat grounding system is indeed diverting the electrical current in the canal. Since the blast mat grounding system is composed of all metallic conductors, it is a much lower resistance than the water and canal walls, making it a preferred circuit for the canal current. This reduces the electrical current available downstream to cause sparking. Voltages need not be reduced for the current to be reduced. Voltage is potential for current flow, but does not guarantee current flow. The lack of sparking even at higher voltage potential differences indicates that there was insufficient current for sparking. This proves that the blast mat grounding system is reducing the current flow beyond the RNA. It also indicates that measuring only voltages is insufficient to fully capture the causes of the sparking. Any future testing should also include current measurements.

The conductivity of the canal water was unusually high during the February testing. On both days, the conductivity was over 3,000 µS/cm. The average conductivity measured during other testing at Barrier IIA and the demonstration barrier is approximately 900 µS/cm. The higher conductivity required a larger current output from the barrier pulsers to maintain a similar voltage in the water. For example, on 2 June 2006 Pulser 1 produced 2,900 amperes of current to maintain a nominal 1 volt/inch gradient between the S3 and S4 arrays for configuration I Normal. However, on 27 February Pulser 1 had to produce over 5,000 amperes for each of the three I Normal 1 volt/inch test runs. Since greater currents were generated in the water, the February tests were completed when sparking was even more likely than in the 2006 tests. That no sparking occurred even at these higher currents is further evidence that the blast mat grounding system is performing effectively.

Configuration I Normal is the best operating configuration identified because it allows Barrier IIA to be operated as originally designed, with the addition of a current grounding system comprised of the blast mats to the south and the Barrier IIB electrodes to the north. While the field strength observed during the I Synchronous field strength mapping was slightly lower than for I Normal, the differences outside of the RNA are negligible. Also, I Normal allows more operational flexibility and redundancy as the electrodes may be powered by two of the three pulsers, while synchronized pulsing is dependent on all arrays being powered by Pulser 2. The higher strength electric field between the active IIA electrodes and the IIB electrodes during I Normal operation is acceptable because this area is within the RNA.

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CONCLUSIONS AND RECOMMENDATIONS

Barrier IIA may be operated in the I Normal configuration at a maximum voltage of up to 2 volts/inch without creating sparking at the Midwest Generation fleeting area. While an electric field can be detected above background levels south of the RNA during barrier operation, there is not sufficient current south of the RNA to generate sparking during fleeting operations.

Tests have not been done on a tow long enough to have one end next to or within the Midwest Generation fleeting area while the other end is still over the active electrodes. There is concern that sparking could occur if such long tows contact barges in the fleeting area. It has been suggested that this concern be eliminated by installing a protection cell north of the fleeting area, but navigation interests have indicated they find such a cell undesirable. Further testing of the sparking potential of a long tow should be completed. Until such testing is completed, it should be conservatively assumed that sparking would occur in a long tow collision with barges south of the RNA. A long tow testing program should also examine the electrical effects on a tow if it spans Barrier IIA and the demonstration barrier while both barriers are operational.

Operation of Barrier IIA in the I Normal configuration at a maximum in-water voltage of 1 volt/inch has no impact on the corrosion potential of barges moored in the fleeting area.

It is safe to operate Barrier IIA in Configuration I Normal at a maximum in-water voltage of 1 volt/inch if bow boats are provided for red flag tows that are long enough to simultaneously be over the active electrodes and south of the RNA. Red flag tows are tows that carry flammable or explosive cargoes. Additional sparking potential testing with long tows should be completed to verify the need for bow boats. Additional sparking and corrosion potential testing should be completed to verify the safety of operating at higher in-water voltages than 1 volt/inch.

ACKNOWLEDGEMENTS

The U.S. Army Corps of Engineers thanks ARTCO for providing barges and towboat operations during sparking potential and corrosion testing, Midwest Generation for providing use of their fleeting area during sparking potential and corrosion testing, and Material Service Corporation for providing mooring space for Corps boats throughout all tests.

Dispersal Barrier IIA February 2007 Sparking Potential, Corrosion Potential, and Electric Field Strength Testing

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Table 1. Listing of Sparking Potential Tests Date/Time Configuration/Figure Fish Barrier Operating

Parameters Observations and Notes

27 FEB 2007

900 – 1100 N/A Fish Barrier IIA turned off.

Sparking potential testing using the series configuration as shown in Figure 3. Voltage data taken between the moving and fixed barge to measure and observe background (ambient) conditions. (Record designation Runs 1 and 2.)

27 FEB 2007

900 – 1100

Configuration I (Normal) Figure 7

S1 & S2 (Pulser 3) 442 V, 2083 A S3 & S4 (Pulser 1) 833 V, 5449 A

Sparking potential testing using the series configuration as shown in Figure 3. This is the “normal” operating condition to achieve a nominal

0.5 volt/inch voltage gradient between S1/S2 and a nominal 1 volt/inch gradient between S3/S4. Barges were “bumped” two times; no sparking was observed. (Record designation Run 3.)

27 FEB 2007

900 – 1100

Configuration I (Normal)

(S3/S4 Increased Voltage) Figure 7

S1 & S2 (Pulser 3) 447 V, 2100 A S3 & S4 (Pulser 1) 1640 V, 10780 A

Sparking potential testing using the series configuration as shown in Figure 3. This was an “increased” operating condition to achieve a nominal 0.5 volt/inch voltage gradient between S1/S2 and a nominal 2.0 volt/inch gradient between S3/S4. Barges were “bumped” three times; no sparking was observed. (Record designation Run 4.)

27 FEB 2007

900 – 1100

Configuration I (Synchronous)

Figure 7

S1 & S2 (Pulser 2) 843 V, 8082 A S3 & S4 (Pulser 2) 843 V, 8082 A S1/S2 opposite polarity of S3/S4

Sparking potential testing using the series configuration as shown in Figure 3. This was an “alternative” operating condition using synchronized pulsing. Pulser settings resulted in a nominal 1.0 volt/inch voltage gradient between S1/S2 and a nominal 1.0 volt/inch gradient between S3/S4. Barges were “bumped” three times; no sparking was observed. (Record designation Run 5.)

27 FEB 2007

900 – 1100

Configuration I (Synchronous)

(Increased Voltage) Figure 7

S1 & S2 (Pulser 2) 1263 V, 12190 A S3 & S4 (Pulser 2) 1263 V, 12190 A S1/S2 opposite polarity of S3/S4

Sparking potential testing using the series configuration as shown in Figure 3. This was an “alternative” operating condition using synchronized pulsing. Pulser settings resulted in a nominal 1.5 volt/inch voltage gradient between S1/S2 and a nominal 1.5 volt/inch gradient between S3/S4. Barges were “bumped” three times; no sparking was observed. (Record designation Run 6.)

27 FEB 2007

900 – 1100

Configuration E (Synchronous)

Figure 8

S1 & S2 (Pulser 2) 846 V, 8052 A S3 & S4 (Pulser 2) 846 V, 8052 A S1/S2 opposite polarity of S3/S4

Sparking potential testing using the series configuration as shown in Figure 3. This was an “alternative” operating condition using synchronized pulsing. Pulser settings resulted in a nominal 1.0 volt/inch voltage gradient between S1/S2 and a nominal 1.0 volt/inch gradient between S3/S4. Barges were “bumped” two times; no sparking was observed. (Record designation Run 7.)

27 FEB 2007

1200 – 1400 N/A Fish Barrier IIA turned off.

Sparking potential testing using the parallel configuration as shown in Figure 4. Tow was positioned at the center of the barge and perpendicular. Barge contacts were not good so the tow was repositioned. Barges were “bumped” two times; no sparking was observed. (Record designation Run 8.)

Dispersal Barrier IIA February 2007 Sparking Potential, Corrosion Potential, and Electric Field Strength Testing

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Date/Time Configuration/Figure Fish Barrier Operating Parameters

Observations and Notes

27 FEB 2007

1200 – 1400 N/A Fish Barrier IIA turned off.

Sparking potential testing using the parallel configuration as shown in Figure 4. To assure good barge contacts the tow was repositioned to the north end and perpendicular to barge. Set of barge contact runs to measure and observe background (ambient) conditions. Barges were “bumped” two times; no sparking was observed. (Record designation Run 9.)

27 FEB 2007

1200 – 1400

Configuration E (Synchronous)

Figure 8

S1 & S2 (Pulser 2) 836 V, 8394 A S3 & S4 (Pulser 2) 836 V, 8394 A S1/S2 opposite polarity of S3/S4

Sparking potential testing using the parallel configuration as shown in Figure 4. This was an “alternative” operating condition using synchronized pulsing. Pulser settings resulted in a nominal 1.0 volt/inch voltage gradient between S1/S2 and a nominal 1.0 volt/inch gradient between S3/S4. Barges were “bumped” three times; no sparking was observed. (Record designation Run 10.)

27 FEB 2007

1200 – 1400

Configuration I (Normal) Figure 7

S1 & S2 (Pulser 3) 443 V, 2159 A S3 & S4 (Pulser 1) 832 V, 5596 A

Sparking potential testing using the parallel configuration as shown in Figure 4. This is a “normal” operating condition to achieve a nominal 0.5 volt/inch voltage gradient between S1/S2 and a nominal 1.0 volt/inch gradient between S3/S4. Barges were “bumped” three times; no sparking was observed. (Record designation Run 11.)

27 FEB 2007

1200 – 1400

Configuration I (Normal)

(S3/S4 Increased Voltage) Figure 7

S1 & S2 (Pulser 3) 444 V, 2153 A S3 & S4 (Pulser 1) 1635 V, 11180 A

Sparking potential testing using the parallel configuration as shown in Figure 4. This was an “increased” operating condition to achieve a nominal 0.5 volt/inch voltage gradient between S1/S2 and a nominal 2.0 volt/inch gradient between S3/S4. Barges were “bumped” three times; no sparking was observed. (Record designation Run 12.)

27 FEB 2007

1200 – 1400

Configuration I (Synchronous)

Figure 7

S1 & S2 (Pulser 2) 834 V, 8462 A S3 & S4 (Pulser 2) 834 V, 8462 A S1/S2 opposite polarity of S3/S4

Sparking potential testing using the parallel configuration as shown in Figure 4. This was an “alternative” operating condition using synchronized pulsing. Pulser settings resulted in a nominal 1.0 volt/inch gradient between S3/S4. Barges were “bumped” five times; sparks were observed during two of the bumps. (Record designation Run 13.)

27 FEB 2007

1200 – 1400

Configuration I (Synchronous)

(Increased Voltage) Figure 7

S1 & S2 (Pulser 2) 1267 V, 12450 A S3 & S4 (Pulser 2) 1267 V, 12450 A S1/S2 opposite polarity of S3/S4

Sparking potential testing using the parallel configuration as shown in Figure 4. This was an “alternative” operating condition using synchronized pulsing. Pulser settings resulted in a nominal 1.5 volt/inch voltage gradient between S1/S2 and a nominal 1.5 volt/inch gradient between S3/S4. Barges were “bumped” two times; no sparking was observed. (Record designation Run 14.)

27 FEB 2007

1500 – 1700 N/A Fish Barrier IIA turned off.

Sparking potential testing using the inserting barge configuration as shown in Figure 5. Set of barge contact runs to measure and observe background (ambient) conditions. Barges were “bumped” four times; no sparking was observed.. (Record designation Run 15.)

Dispersal Barrier IIA February 2007 Sparking Potential, Corrosion Potential, and Electric Field Strength Testing

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Date/Time Configuration/Figure Fish Barrier Operating Parameters

Observations and Notes

27 FEB 2007

1500 – 1700

Configuration I (Synchronous)

Figure 7

S1 & S2 (Pulser 2) 836 V, 8384 A S3 & S4 (Pulser 2) 836 V, 8384 A S1/S2 opposite polarity of S3/S4

Sparking potential testing using the inserting barge configuration as shown in Figure 5. This was an “alternative” operating condition using synchronized pulsing. Pulser settings resulted in a nominal 1.0 volt/inch voltage gradient between S1/S2 and a nominal 1.0 volt/inch gradient between S3/S4. Barges were “bumped” five times; no sparking was observed. (Record designation Run 16.)

27 FEB 2007

1500 – 1700

Configuration I (Synchronous)

(Increased Voltage) Figure 7

S1 & S2 (Pulser 2) 1265 V, 12650 A S3 & S4 (Pulser 2) 1265 V, 12650 A S1/S2 opposite polarity of S3/S4

Sparking potential testing using the inserting barge configuration as shown in Figure 5. This was an “alternative” operating condition using synchronized pulsing. Pulser settings resulted in a nominal 1.5 volt/inch voltage gradient between S1/S2 and a nominal 1.5 volt/inch gradient between S3/S4. Barges were “bumped” three times; no sparking was observed. (Record designation Run 17.)

27 FEB 2007

1500 – 1700

Configuration I (Normal) Figure 7

S1 & S2 (Pulser 3) 446 V, 2179 A S3 & S4 (Pulser 1) 825 V, 5771 A

Sparking potential testing using the inserting barge configuration as shown in Figure 5. This is a “normal” operating condition to achieve a nominal 0.5 volt/inch voltage gradient between S1/S2 and a nominal 1.0 volt/inch gradient between S3/S4. Barges were “bumped” four times; no sparking was observed. (Record designation Run 18.)

27 FEB 2007

1500 – 1700

Configuration I (Normal)

(S3/S4 Increased Voltage) Figure 7

S1 & S2 (Pulser 3) 449 V, 2206 A S3 & S4 (Pulser 1) 1635 V, 11210 A

Sparking potential testing using the inserting barge configuration as shown in Figure 5. This was an “increased” operating condition to achieve a nominal 0.5 volt/inch voltage gradient between S1/S2 and a nominal 2.0 volt/inch gradient between S3/S4. Barges were “bumped” three times; no sparking was observed. (Record designation Run 19.)

27 FEB 2007

1500 – 1700

Configuration E (Synchronous)

Figure 8

S1 & S2 (Pulser 2) 842 V, 8267 A S3 & S4 (Pulser 2) 842 V, 8267 A S1/S2 opposite polarity of S3/S4

Sparking potential testing using the inserting barge configuration as shown in Figure 5. This was an “alternative” operating condition using synchronized pulsing. Pulser settings resulted in a nominal 1.0 volt/inch voltage gradient between S1/S2 and a nominal 1.0 volt/inch gradient between S3/S4. Barges were “bumped” three times; no sparking was observed. (Record designation Run 20.)

27 FEB 2007

1500 – 1700

Configuration E (Synchronous)

(Increased Voltage) Figure 8

S1 & S2 (Pulser 2) 1263 V, 12520 A S3 & S4 (Pulser 2) 1263 V, 12520 A S1/S2 opposite polarity of S3/S4

Sparking potential testing using the inserting barge configuration as shown in Figure 5. This was an “alternative” operating condition to reduce the field strength south of the bridge. Pulser settings resulted in a nominal 1.5 volt/inch voltage gradient between S1/S2 and a nominal 1.5 volt/inch gradient between S3/S4. Barges were “bumped” three times, no sparking was observed. (Record designation Run 21.)

28 FEB 2007

900 – 1100 N/A Fish Barrier IIA turned off.

Sparking potential testing using the angled tow configuration as shown in Figure 6. Set of barge contact runs to measure and observe background (ambient) conditions. Barges were “bumped” three times; no sparking was observed. (Record designation Run 1.)

Dispersal Barrier IIA February 2007 Sparking Potential, Corrosion Potential, and Electric Field Strength Testing

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Date/Time Configuration/Figure Fish Barrier Operating Parameters

Observations and Notes

28 FEB 2007

900 – 1100

Configuration E (Synchronous)

Figure 8

S1 & S2 (Pulser 2) 839 V, 7252 A S3 & S4 (Pulser 2) 839 V, 7252 A S1/S2 opposite polarity of S3/S4

Sparking potential testing using the angled tow configuration as shown in Figure 6. This was an “alternative” operating condition using synchronized pulsing. Pulser settings resulted in a nominal 1.0 volt/inch voltage gradient between S1/S2 and a nominal 1.0 volt/inch gradient between S3/S4. Barges were “bumped” three times; no sparking was observed. (Record designation Run 2.)

28 FEB 2007

900 – 1100

Configuration E (Synchronous)

(Increased Voltage) Figure 8

S1 & S2 (Pulser 2) 1254 V, 10970 A S3 & S4 (Pulser 2) 1254 V, 10970 A S1/S2 opposite polarity of S3/S4

Sparking potential testing using the angled tow configuration as shown in Figure 6. This was an “alternative” operating condition using synchronized pulsing. Pulser settings resulted in a nominal 1.5 volt/inch voltage gradient between S1/S2 and a nominal 1.5 volt/inch gradient between S3/S4. Barges were “bumped” three times; no sparking was observed. (Record designation Run 3.)

28 FEB 2007

900 – 1100

Configuration I (Normal) Figure 7

S1 & S2 (Pulser 3) 440 V, 1917 A S3 & S4 (Pulser 1) 830 V, 4932 A

Sparking potential testing using the angled tow configuration as shown in Figure 6. This is a “normal” operating condition to achieve a nominal 0.5 volt/inch voltage gradient between S1/S2 and a nominal 1.0 volt/inch gradient between S3/S4. Barges were “bumped” three times; no sparking was observed. (Record designation Run 4.)

28 FEB 2007

900 – 1100

Configuration I (Normal)

(S3/S4 Increased Voltage) Figure 7

S1 & S2 (Pulser 3) 443 V, 1894 A S3 & S4 (Pulser 1) 1628 V, 9668 A

Sparking potential testing using the angled tow configuration as shown in Figure 6. This was an “increased” operating condition to achieve a nominal 0.5 volt/inch voltage gradient between S1/S2 and a nominal 2.0 volt/inch gradient between S3/S4. Barges were “bumped” three times; no sparking was observed. (Record designation Run 5.)

28 FEB 2007

900 – 1100

Configuration I (Synchronous)

Figure 7

S1 & S2 (Pulser 2) 843 V, 7301 A S3 & S4 (Pulser 2) 843 V, 7301 A S1/S2 opposite polarity of S3/S4

Sparking potential testing using the angled tow configuration as shown in Figure 6. This was an “alternative” operating using synchronized pulsing. Pulser settings resulted in a nominal 1.0 volt/inch voltage gradient between S1/S2 and a nominal 1.0 volt/inch gradient between S3/S4. Barges were “bumped” three times; no sparking was observed.

(Record designation Run 6.)

28 FEB 2007

900 – 1100

Configuration I (Synchronous)

(Increased Voltage) Figure 7

S1 & S2 (Pulser 2) 1253 V, 10820 A S3 & S4 (Pulser 2) 1253 V, 10820 A S1/S2 opposite polarity of S3/S4

Sparking potential testing using the angled tow configuration as shown in Figure 6. This was an “alternative” operating condition using synchronized pulsing. Pulser settings resulted in a nominal 1.5 volt/inch voltage gradient between S1/S2 and a nominal 1.5 volt/inch gradient between S3/S4. Barges were “bumped” two times; no sparking was observed. (Record designation Run 7.)

Dispersal Barrier IIA February 2007 Sparking Potential, Corrosion Potential, and Electric Field Strength Testing

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Table 2. Peak Voltage Gradients During Sparking Potential Tests.

Date Run # Barrier Operating Configuration Potential Difference Between

Moving Barge & Barge Contacting (Volts)

Sparking Observed?

(Yes/No)

If Yes to Sparking; On

How Many Bumps?

Background/Ambient 27-Feb-07 Run 1&2 Off (Background) 0.3 N Not Observed Barges in Series 27-Feb-07 Run 3 I Normal 800 V (1 volt/inch) 1.6 N Not Observed

Figure 3 27-Feb-07 Run 4 I Normal 1600V (2 volts/inch) 2.8 N Not Observed 27-Feb-07 Run 5 I Synchronous 800V (1 volt/inch) 0.8 N Not Observed 27-Feb-07 Run 6 I Synchronous 1200V (1.5 volts/inch) 1.2 N Not Observed 27-Feb-07 Run 7 E Synchronous 800V (1 volt/inch) 0.96 N Not Observed

Background/Ambient 27-Feb-07 Run 8 Off (Background) 0.03 N Not Observed Background/Ambient 27-Feb-07 Run 9 Off (Background) 0.03 N Not Observed

Barges in Parallel 27-Feb-07 Run 10 E Synchronous 800V (1 volt/inch) 0.09 N Not Observed Figure 4 27-Feb-07 Run 11 I Normal 800 V (1 volt/inch) 0.15 N Not Observed

27-Feb-07 Run 12 I Normal 1600V (2 volts/inch) 0.3 N Not Observed 27-Feb-07 Run 13 I Synchronous 800V (1 volt/inch) 0.05 Y 2 of 5 Bumps 27-Feb-07 Run 14 I Synchronous 1200V (1.5 volts/inch) 0.08 N Not Observed

Background/Ambient 27-Feb-07 Run 15 Off (Background) 0.09 N Not Observed Inserting a Barge 27-Feb-07 Run 16 I Synchronous 800V (1 volt/inch) 0.1 N Not Observed

Figure 5 27-Feb-07 Run 17 I Synchronous 1200V (1.5 volts/inch) 0.6 N Not Observed 27-Feb-07 Run 18 I Normal 800 V (1 volt/inch) 0.1 N Not Observed 27-Feb-07 Run 19 I Normal 1600V (2 volts/inch) 0.4 N Not Observed 27-Feb-07 Run 20 E Synchronous 800V (1 volt/inch) 0.1 N Not Observed 27-Feb-07 Run 21 E Synchronous 1200V (1.5 volts/inch) 1.4 N Not Observed

Background/Ambient 28-Feb-07 Run 1 Off (Background) 0.75 N Not Observed Angled Tow 28-Feb-07 Run 2 E Synchronous 800V (1 volt/inch) 4.6 N Not Observed

Figure 6 28-Feb-07 Run 3 E Synchronous 1200V (1.5 volts/inch) 6.5 N Not Observed 28-Feb-07 Run 4 I Normal 800 V (1 volt/inch) 4.6 N Not Observed 28-Feb-07 Run 5 I Normal 1600V (2 volts/inch) >10 N Not Observed 28-Feb-07 Run 6 I Synchronous 800V (1 volt/inch) 3.4 N Not Observed 28-Feb-07 Run 7 I Synchronous 1200V (1.5 volts/inch) 5 N Not Observed

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Table 3. Environmental Conditions during Field Testing.

Date Time Air

Temperature (°F)

Relative Humidity

Precipitation (in)

Water Temperature (°F)

Water Conductivity (ppm TDS)

[µS/cm] 27 February 2007 930 36 62 0.00 NR NR 27 February 2007 1100 39 57 0.00 NR NR 27 February 2007 1240 37 60 0.00 NR NR 27 February 2007 1330 38 58 0.00 NR NR 27 February 2007 1400 NR NR NR 46 2190 [3428] 27 February 2007 1500 37 58 0.00 NR NR 27 February 2007 1545 36 61 0.00 NR NR 28 February 2007 930 36 64 0.00 NR NR 28 February 2007 1100 43 49 0.00 46 2020 [3150]

Table 4. Barge Corrosion Potential Measurements.

Date Time Barrier Operating Configuration

Potential (-mV) Measurement Location

27 February 2007 1235 Off 333 NE corner of north barge 27 February 2007 1325 I Normal 800 V 342 NE corner of north barge

Table 5. General Corrosion Rates for Steel in Fresh Water*

Potential between steel and Ag/AgCl reference electrode

(-mV)

Corrosion Rate

Min Max

590 690 Extremely High

490 590 High

340 490 Moderate to Low

90 340 High

* Fresh water is defined as having either greater than 300 Ω-cm resistivity or less than 3.3 S/cm conductivity.

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Table 6. Listing of Barrier IIA Field Mapping Runs

Date/Time Configuration/ Figure

Fish Barrier Operating Parameters

Observations and Notes

28 FEB 2007

1200 – 1400

Configuration I (Normal) Figure 7

S1 & S2 (Pulser 3) 441 V, 1947 A S3 & S4 (Pulser 1) 829 V, 5078 A

Field mapping using Figure 7 configuration. This is a “normal” operating condition to achieve a nominal 0.5 volt/inch voltage gradient between S1/S2 and a nominal 1.0 volt/inch gradient between S3/S4. Results presented in Figure 12. (Record designation Runs 1 through 6.)

28 FEB 2007

1400 – 1500 N/A Fish Barrier IIA turned off. Field mapping of background (ambient) conditions. Results presented in

Figure 11. (Record designation Runs 7 through 9.)

28 FEB 2007

1500 – 1700

Configuration I (Normal)

(S3/S4 Increased Voltage) Figure 7

S1 & S2 (Pulser 3) 443 V, 1977 A S3 & S4 (Pulser 1) 1635 V, 10210 A

Field mapping using Figure 7 configuration. This was an “increased” operating condition to achieve a nominal 0.5 volt/inch voltage gradient between S1/S2 and a nominal 2.0 volt/inch gradient between S3/S4. Results presented in Figure 13. (Record designation Runs 10 through 12.)

28 FEB 2007

1500 – 1700

Configuration I (Synchronous)

Figure 7

S1 & S2 (Pulser 2) 831 V, 7701 A S3 & S4 (Pulser 2) 831 V, 7701 A S1/S2 opposite polarity of S3/S4

Field mapping using Figure 7 configuration. This was an “alternative” operating condition using synchronized pulsing. Pulser settings resulted in a nominal 1.0 volt/inch voltage gradient between S1/S2 and a nominal 1.0 volt/inch gradient between S3/S4. Results presented in Figure 14. (Record designation Runs 13 through 15. Runs 14 and 15 were shortened because a tow parked in the canal opposite the loading dock.)

28 FEB 2007

1500 – 1700

Configuration I (Synchronous)

(Increased Voltage) Figure 7

S1 & S2 (Pulser 2) 1258 V, 11480 A S3 & S4 (Pulser 2) 1258 V, 11480 A S1/S2 opposite polarity of S3/S4

Field mapping using Figure 7 configuration. This was an “alternative” operating condition using synchronized pulsing. Pulser settings resulted in a nominal 1.5 volt/inch voltage gradient between S1/S2 and a nominal 1.5 volt/inch gradient between S3/S4. Results presented in Figure 15. (Record designation Runs 16 through 18.)

28 FEB 2007

1500 – 1700

Configuration E (Synchronous)

Figure 8

S1 & S2 (Pulser 2) 843 V, 7652 A S3 & S4 (Pulser 2) 843 V, 7652 A S1/S2 opposite polarity of S3/S4

Field mapping using Figure 8 configuration. This was an “alternative” operating using synchronized pulsing. Pulser settings resulted in a nominal

1.0 volt/inch voltage gradient between S1/S2 and a nominal 1.0 volt/inch gradient between S3/S4. Results presented in Figure 16. (Record designation Runs 19 through 21.)

28 FEB 2007

1500 – 1700

Configuration E (Synchronous)

(Increased Voltage) Figure 8

S1 & S2 (Pulser 2) 1255 V, 11440 A S3 & S4 (Pulser 2) 1255 V, 11440 A S1/S2 opposite polarity of S3/S4

Field mapping using Figure 8 configuration. This was an “alternative” operating condition using synchronized pulsing. Pulser settings resulted in a nominal 1.5 volt/inch voltage gradient between S1/S2 and a nominal 1.5 volt/inch gradient between S3/S4. Results presented in Figure 1.7 (Record designation Runs 22 through 24.) ()

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Table 7. Peak Pulse Voltage Gradient (mV/in) at Romeo Road Bridge.

Date Configuration Runs Depth South Side of Bridge

West Bank Center East Bank 28 FEB 2007 I Normal 800V 1 - 6 2' 15.0 ± 4.5 11.8 ± 2.6 10.2 ± 2.8

(1 volt/inch) 4' 13.4 ± 3.3 12.3 ± 3.2 11.3 ± 2.7 7' 13.2 ± 2.7 11.8 ± 2.7 10.3 ± 2.2 15' 13.3 ± 2.8 11.8 ± 2.7 10.4 ± 3.0

28 FEB 2007 N/A * 7 - 9 2' 0.00± 3.3 0.00± 4.0 0.00± 4.6

4' 0.00± 5.7 0.00± 5.7 0.00± 7.6 7' 0.00± 5.6 0.00± 4.8 0.00± 5.3 15' 0.00± 4.5 0.00± 4.8 0.00± 4.9

28 FEB 2007 I Normal 1600V 10 - 12 2' 22.6 ± 9.6 18.3 ± 7.5 14.8 ± 5.5 (2 volts/inch) 4' 21.3 ± 9.1 20.2 ± 7.4 16.5 ± 5.6 7' 21.8 ± 9.5 18.0 ± 7.1 16.1 ± 5.8 15' 21.8 ± 9.4 18.5 ± 7.5 16.1 ± 5.7

28 FEB 2007 I Synchronous 800V 13 - 15 2' 10.1 ± 1.2 8.6 ± 1.2 8.1 ± 0.9 (1 volt/inch) 4' 10.0 ± 2.1 7.7 ± 1.9 9.6 ± 1.4 7' 11.2 ± 1.0 9.4 ± 1.3 8.6 ± 0.8 15' 10.8 ± 1.0 9.1 ± 1.0 8.3 ± 2.5

28 FEB 2007 I Synchronous 1200V 16 - 18 2' 15.0 ± 1.2 12.5 ± 1.7 11.1 ± 2.3 (1.5 volts/inch) 4' 13.6 ± 1.6 14.2 ± 1.3 12.4 ± 1.3 7' 14.4 ± 1.1 13.2 ± 1.3 11.1 ± 0.8 15' 14.5 ± 1.6 12.9 ± 1.2 11.3 ± 0.9

28 FEB 2007 E Synchronous 800V 19 - 21 2' 13.6 ± 0.8 11.5 ± 2.3 10.4 ± 2.0 (1 volt/inch) 4' 13.4 ± 2.0 11.9 ± 1.3 11.2 ± 1.2 7' 13.5 ± 1.0 11.6 ± 1.5 10.6 ± 1.1 15' 12.7 ± 0.8 12.1 ± 1.8 10.5 ± 1.0

28 FEB 2007 E Synchronous 1200V 22 - 24 2' 19.7 ± 0.9 16.9 ± 1.4 15.3 ± 1.9 (1.5 volts/inch) 4' 18.8 ± 2.1 18.4 ± 1.5 17.4 ± 2.5 7' 19.6 ± 1.0 16.8 ± 1.4 16.0 ± 2.3 15' 19.6 ± 1.1 17.1 ± 1.4 14.8 ± 2.2

Dispersal Barrier IIA February 2007 Sparking Potential, Corrosion Potential, and Electric Field Strength Testing

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Figure 1. Relative Location of Demonstration Barrier and Barrier II.

Dispersal Barrier IIA February 2007 Sparking Potential, Corrosion Potential, and Electric Field Strength Testing

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Figure 2. Fish Barrier II and Blast Mat Grounding System in February 2007.

Dispersal Barrier IIA February 2007 Sparking Potential, Corrosion Potential, and Electric Field Strength Testing

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Figure 7. Barrier IIA Operating Configuration ‘I’.

Dispersal Barrier IIA February 2007 Sparking Potential, Corrosion Potential, and Electric Field Strength Testing

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Figure 8. Barrier IIA Operating Configuration ‘E’.

Dispersal Barrier IIA February 2007 Sparking Potential, Corrosion Potential, and Electric Field Strength Testing

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208"

2'

Fiberglass Boat (Boston Whaler)

208"

2'

Fiberglass Boat (Boston Whaler)

Figure 9. Half-cell array suspended from fiberglass (non-conductive) boat.

Figure 10. Field measurement paths in canal.

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Po te nt ia l ( m V/ in ch

West Bank Center East Bank

X 2-foot ∆ 4-foot

○ 7-foot ─ 15-foot

Configuration I Normal 800V

B ackground

Configuration I Normal 1600V

Configuration I Synchronous 800V

Configuration I Synchronous 1200V Configuration

E Synchronous 800V

Configuration E Synchronous 1200V

Po te nt ia l ( m V/ in ch

West Bank Center East Bank

X 2-foot ∆ 4-foot

○ 7-foot ─ 15-foot

Configuration I Normal 800V

B ackground

Configuration I Normal 1600V

Configuration I Synchronous 800V

Configuration I Synchronous 1200V Configuration

E Synchronous 800V

Configuration E Synchronous 1200V

Figure 18. Graphical representation of electric field strength measurements at the south end of the Romeo Road Bridge by configuration, location and depth.

Page 34 of 34 24 October 2006

Appendix - INSTRUMENTATION

The most important test equipment used for this project is listed below.

1) Pacific Instruments 6000 Series Data Acquisition System with 6603-3 Plug-in

2) Tektronix P5200 High Voltage Digital Probe

3) Fluke 123 Digital Scopemeter with 20 MHz Bandwidth

4) ARMS enhanced Ike 304

The Pacific Instruments 6000 Series Data Acquisition System was used to continuously measure and record the voltage differentials. The Pacific was chosen because of its multiple independent channel capabilities and its high sampling rate. The Pacific was connected to a laptop computer through a GPIB interface and the data was immediately transferred to the computer for storage.

Because of the high sample rate and long scan times, barrier pulses were easily captured. When interpreting the Pacific data, the individual pulses and the ‘envelope’ (overall trend of the peak values) of the…